Explosive-engine.



E. J. WOOLF.

EXPLOSIVE ENGINE.

APPLICATION FILED M1127, 1908 1,121,153. Patented Dec.15,1914.

2 SHEETS-332KB 2.

oron.

ELLIS J. WOOLF, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO THE WOOLF VALVEGEAR,

COMPANY, OF MINNEAPOLIQ,

MINNESOTA, A CORPORATION OF MINNESOTA.

BICPLOSIVE-ENGINE.

Specification of Letters Patent.

Patented Dec. 15, 19142.

Application filed January 27, 1908. Serial No. 412,772.

To all whom it ma concern:

Be it known tliat I, Ems J. WooLF, a citizen of the United States, residng at Minneapolis, in the county of Hennepm and Stateof Minnesota, haveinvented certain new and useful Improvements in Explosive- Engines; andI do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

My invention has for its object to provide an efiicient two-cycleexplosive engine; and to this end, the invention consists of the noveldevices and combinations of devices hereinafter described and defined inthe claims.

Some of the most important features of invention herein disclosed andclaimed are disclosed in my co-pending application S. N. 39%,030, filedSeptember 23, 1907, entitled Explosive engine.

The accompanying drawings illustrate the invention as embodied in atwo-unit twoc vcle engine. In said drawings, like notations refer tolike parts throughout the sev eral views.

Referring to the drawings; Figure 1 is a vertical central sectionlengthwise of the crank shaft with the pistons at the opposite extremesof their travel, some parts being broken away and some parts shown inelevation. Fig. 2 is a detail in section showing the ring valve of theright hand unit in the same position as Fig. 1, but with the piston asit appears after moving downward far enough to open the transfer port,or to the limit of its free movement in respect to the ring valve. Fig.3 is a sectional View in the same plane as Fig. 1, but with the partsshown in the position occupied after the right hand piston has moveddownward far enough to bring its suction port into position forcooperation with the transfer ports, for the scavenging action; and Fig.4 is a detail in horizontal section through portions of the connectedengines on the line :2 a of Fig. 3, showing the common port connectingthe differential spaces of the two units and the valve through which thescavenging charge of air or air and water, is drawn.

A double chamber base casting 1 and a pair of differential cylindercastings 2 are rigidly secured together with suitably packed joints,

To each of the differential cylinder castings 2 is rigidly secured anexplosion cylinder casting 3. The castings l and 2 are of suchconstruction that when joined together they inclose the crank shaft atand afford two chambers surrounding the same, and which serve as thebase or compression chambers 5. The crank shaft 4 is shown as providedwith a suitable fly wheel 6.

The casting 3 is of the proper form to afford the main or explosionportion ofthe smaller member of the differential cylinders; and each ofthe castings 2 is of the proper form to afford a part of the smallermember of the differential cylinders and to aflord the whole of thelarger member of said differential cylinders. In the differentialcylinders afforded by the castings 2 and 3 is mounted a correspondingdifferential piston 7 connected by a rod 8 to one of the cranks 9 of theshaft 4. The two cranks 9 are shown as set 180 degrees apart. Thesmaller member of the differential piston 7 is of hollow or trunk-likeform, and the crank shaft end thereof opens into the com pressionchamber 5.

The numeral 10 represents the differential space or chamber defined bythe walls of the differential cylinders and pistons.

The castings 2 and 3 are so constructed that, when joined together attheir parting flanges, they afford between the sections of the explosioncylinder wall an exhaust port 11 which completely encircles saidcylinder and leads to a large annular exhaust chard ber 12 formed in thelower end portion of the casting 2 and provided with the ordinaryexhaust pipe opening 13. The piston 7 has in its tmnk a transfer port 1%which is a complete circle with the exception of the bridges therein.The lower end of each casting 2 is of the proper form to afford thereina cooperating transfer port 15 directly inward of the exhaust chamber 12which is also a complete circle, with the errception of the bridgestherein which support the adjacent inner wall of the explosion cylinder.Between the said piston and the inner wall of the explosion cylinder islocated a ring valve 16 to control said transfer ports 14 and 15, somounted that it bears tightly against the cylinder wall and that theiston will move through the valve. for a limited distance, and then pickup and -bers 5, in the base carry the said valve therewith during therest of its travel in both directions. For thisvpurpose, thesaid ringvalve 16 is preferably a splitring which will tightly hug the cylindert-wall under its own tension; and, as shown, this ring valve 16 is ofshape with the horizontal flange of the L turned inward and workingfreely in arecess or annular groove 17 formed in the piston 7, with theproper clearance for the required free movement of the piston throughsaid valve. The horizontal flange of the ring valve 16, the height ofthe recess 17, and the height of the transfer port 14 in the piston 7,are so proportioned that the lower end of the ring valve 16 will seatagainst the lower wall of said port'14 coincidently with the seating ofthe.flange 'of said valve against the lower wall of the recess 17. Inthe piston 7 is located a deflector 18 directly inward of the transferport 14.

and extending downward nearly but not quite to the end of the pistonhead. The said piston 7 has an exterior annular recess 19 in its trunkwall which, at the proper time, serves as a suction port for cooperationwith the .said transfer ports 14 and 15 for the scavenging action, aswill later more fully appear.

The casting 3 is of the proper form to afford a water jacket space 20through which cooling water is circulated in the ordinary way. Saidcastings 3 are also each fitted with a suitable sparking plug 21.

Both members of the are fitted with the ordinary packing rings and servetheir customary function; and the only point needing notice, inconnection therewith, is the fact that the two packing rings of thesmaller piston are both located below or nearer the small'end of thepiston? than the ring valve 16.

The differential cylinder castings 2 of the two units abut each other,and each thereof is provided with one section of a port 22 connectingthe two differential spaces or chambers 10, as best shown in Fig. 4.combined air and water supply valve 23, of a well known type,

is in communication with said port 22 by a short pipe 24, as shown insaid Fig. 4, to supply air or air and water for scavenging purposes. Thesaid combined air and water valve 23 is operated under suction producedby the crank shaft ends of the differential pistons, as will presentlymore fully' appear. The'portions of casting 1, are in communication witha valve casing 25 which is fitted with a two-way check valve 26, and thechest of this valve is tapped by supply pipe 27 leading from a suitablesource of ex plosive material, not shown. The valve 26 is operated bythe suction and compression actions of the crank shaft ends of the twovalve 16 has from the position diiferential pistons the compression chamAs shown, the stem of said double check valve 26 has a conical hole 28therein in which works the lower end of a hand screw 29 seated in thecasing 25, central of the said valves travel, and which parts cooperateto limit the closing movements of the said double check valve 26,whenever so desired, for the purposes hereinafter named.

0pemtion.-The cycle of actions will be traced with reference to theright hand unit. Let it be assumed that the compression chamber-5 ofsaid right hand unit contains an explosive mixture previously drawntherein and compressed to charging pressure, and that its explosioncylinder has been exhausted and scavenged. Let it also be noted that thepiston of said right hand unit has completed its upward or explosionstroke and is just ready to start back downward. At this instant, thetransfer ports 14 and 15 are still closed by the ring valve 16. Then, asthe piston moves downward into the position shown in Fig. 2, or to thelimit of its free movement through the ring valve 16, the said ringvalve will remain in its uppermost position, or just as shown in Figs. 1and 2, bearing tightly against the cylinder wall from its own springtension and the pressure thereon from the compressed charge. Otherwisestated, the ring been dropped and the piston moves on through the same,while'traveling shown in Fig. 1 to that shown in Fig. 2. During thissame time, the head ofthe piston has been above the lower end ofthetransfer port 15 of the cylinder; and hence, it follows, that, duringall this time, the transfer ports 14 and 15 have been in communication,and that the charge has beenrushing in from the compression chamber tothe explosion cylinder through the said ports 14 and 15, as shown by thearrows in Fig. 2. In so doing, the charge is made, by the deflector 18,to pass downward against the wall of the piston head and then upwardalong its side walls to the transfer port 14 of the piston, thus gettingthe full benefit of the heat thereof.

differential pistons.

' The lower end of the cylinder port 15 is so shaped that the enteringcharge converges to a central meeting point from all parts of saidannular port 15, and, of necessity, at this point of convergence, thecharge must be thrown vertically downward through the central zone ofthe explosion cylinder, as this is the only available course.

.As soon as the pis n reaches the point she in'inFig. 2, it picks up thering valve 16 and moves the same therewith throughout the remainder ofits downward travel, and the charging action will continue until thepiston head closes the lower end of the transfer port 15, theproportions of the parts being suchthatthe ring valve 16 will close theupper end of said port substantially coincident therewith. This, ofnecessity, leaves the transfer port 15 full of explosive mixture cagedtherein, after the charging action has been completed. Under thecontinued downward movement of the piston, the exhaust port 11 is nextclosed; and, then, the charge within the explosion cylinder iscompressed, and, at the proper time, ignited from the sparking plug 21,and the explosion takes place. When, under this downward movement of thepiston T, the parts reach the position shown in Fig. 3, the suction port19 of the piston 7 will bridge the dividing wall between thedifferential space 10 and the upper end of the cylinder transfer port15, thereby connecting the same; and, at this same time, the transferport 14 of the piston will be open and in registration with the lowerend of said transfer port 15, as shown in said-view; and because of thisrelation of the said ports 14, 15 and 19, the suction action of thecrank shaft end of the differential piston will become operative firstto draw back into the base or compression chamber 5 the explosivemixture which had been caged in the transfer port 15, and, then, to fillthe same with a scavenging charge of air, or air and water, from thedifferential space 10 drawn into the same through the air and watervalve 23 and pipe 24. Under the further downward movement of the piston7 from the position shown in Fig. 3, this scavenging charge will wecaged in the said cylinder port 15 and there remain available forscavenging purposes. As soon as the charge in the explosion chamber hasbeen compressed and exploded, the piston will, of course, instantly movein the opposite direction, or upward, and leave or drop the ring valve16, which will then clamp the cylinder wall, under its own tension,until the piston has moved therethrough to the limit of its freemovement, thus causing the ring valve to close the transfer port 14 ofthe piston; and the piston will then again pick up and carry the ringvalve with it in this port-closed position, throughout the remainder ofthe pistons explosion stroke, or until it returns to the position shownin Fig. 1. In this up ward travel of the piston. under the effect of theexplosion, the gases, of course, act expansively, until the piston headuncovers the exhaust port 11; whereupon, the ex haust will begin andcontinue throughout the remainder of the explosion stroke. Soon afterthe exhaust begins. the piston head will also uncover the lower and ofthe transfer port 15, and the scavenging charge previously cagedtherein. as above noted, will become available for scavcng g purposes.Bearing in mind that this contains more or less water, it issobviousthat the flame or extremely hot gases, still under considerablepressure, will vaporize the water in this scavenging charge, and thesteam generated therefrom, by the expansion thereof, will, when theexhaust pressure gets low enough, rush into the explosion cylinder andthereby thoroughly scavenge the same before the piston reaches the limitof its explosion stroke. In view of the position taken by the ring valve16, immediately after the piston begins to move upward under the effectof the explosion, it follows, as already noted, that said ring valvecloses the transfer port 1st of the piston throughout the whole of theexplosion stroke; and it further follows that there can be no blow backof the exhausting gases through the transfer ports 15 and 14 into thecompression chamber. Hence, with this engine, back explosions areimpossible. WVhatever air, or air and steam, remains in. the cylindertransfer port 15, after the first scavenging action, above noted, hasbeen completed, or after the parts reach the position shown in Fig. 1,will, of necessity, be forced into the explosion cylinder, in advance ofthe new charge, when the piston begins to move downward from theposition shown in Fig. 1 into that shown in Fig. 2, thereby furtherscavenging the cylinder, as the exhaust port 11 remains open throughoutthe entire time of the scavenging and char ing actions. In thisconnection, it shoul be noted, that this transfer port 15 is large, asit completely encircles the cylinder, and is also of considerable heightand width. -The volume of air thus made available for the secondscavenging action is, therefore, considerable; and this provision isdesirable, not only for said scavenging purposes, but to avoid any wasteof the new charge through the exhaust port before the latter is closedto compression. If anything is forced out, it will be air and steam.

The foregoing gives the cycle of actions for the right hand unit,starting from the position there shown under the conditions assumed. Itonly remains to note how those conditions there assumed were secured.This relates simply to the intake for the explosive mixture.

It was assumed that a previously drawn in charge had been compressed inthe chamher 5 of the right hand unit; and, under said assumption, thetwo-way check valve 26 would be: held in its closed position by thepressure therefrom. After the transfer of the compressed charge iseffected, under the downward movement of the piston 7, the suctionaction of the crank shaft end of the piston will begin in thecompression chamvalve 26 will be instantly shifted from the positionshown in Fig. 1 to the osition' shown in Fig. 3, and that the explosivemixture will therefore be drawn into the chamher 5 of the right handunit. When the piston of the right hand unit begins to move upward,under the effect of the explosion in that unit, the piston of the lefthand unit will be moving downward so that the reverse action inrespectto the intake of the 'explosive'mixtur'e will take place, to-wit,

the two-way check valve 26 will be shifted from theposition shown inFig. 3 to the position shown in Fig. 1, and the explosive material willbe entering the left hand compression chamber 5, and the previouslydrawn in mixture in the right hand chamber 5 will be caged therein andcoming under compression. This. completes all the cycle of actions, inall their phases, both in respect to the intake and distribution. Itmust be further .noted, however, that the hand screw 29 enables theclosing movement of the two-way valve 26 to be intercepted, so as toleave any desired degree of leakage from one to the other of thecompression chambers 5, and that, by this means, the volume and pressureof the available charge can be reduced to govern the speed of theengine, or for starting the engine. It must also be obvious that acentri gal governor could be readily applied to the screw stop 29, or,its equivalent, so as to render this governing action automatic.

, Respecting the differential spaces 10, it is worthy of notice that novacuum occurs therein under the movements of the differential pistons,but that the air and Water therein contained will be shifted from one tothe other of said differential spaces alternately through theirconnecting port 22, with the exceptions of such portions thereof as aredrawn into the transfer ports 15 of the two cylindersfor the scavengingaction, under the cooperation of the suction ports 19 with said transferports 14 and 15, as hitherto noted; and, of course, whatever amount isthus drawn into said-ports 15 is replaced in the connected differentialspaces 10 by an equivalent amount drawn in at the same time through thecombined air and water valve 23 and pipe-24 (mammal-s.--Some of theadvantages of the novel distribution valve, disclosed in this engine.have already been noted. For example, attention has been called to thefact that no back explosion into the compression chambers can occur.Another advantage due to this ring valve 16 is that a very largetransfer or charging port is rendered available, so that said port'onlyneeds to be open for a very short time. The transfer port 14, in thepiston, the same, with the exception of the bridge .bythe piston,

" reliable.

entirely encircles walls, and the transfer port 15, in the cylinder,also encircles the bore of the cylinder, with the same kind of anexception; and, hence, the only limit to the circular length of thetransfer or charging ports is the peripher of the piston. It follows,that the heig t of this controlling member 14: of the transfer ports,measured lengthwise of the piston, may be comparatively short. Hence,said port needs only to be open for a very short time to make thecomplete transfer required for a full charge. The throw of the valve 16,i. 6., the free movement of the piston through said ring valve 16-is,therefore, short; and the valve is picked up in eachdirection of thelatters travel, ust after the crank passes its dead center, pr at timeswhen the piston is moving extremely slow. It follows, that the said ringvalve 16 will be picked up by the piston without pounding or noise, as Ihave demonstrated in actual practice. Another important advantage of thesaid ring valve 16, and said annular transfer ports Hand 15, encirclingthe piston and cylinder, is that uniformity of expansion is therebysecured in all parts of the piston and cylinder walls su ject to the hotgases. This uniformity of expansion thus secured elfectually preventsany distortion or cracking of the castings from unequal expansion. A

further advantage of this form of distribution valve is the fact thatthe same can be seated between the piston and cylinder at such a placethat the said ring valve never becomes subject to the hot gases orpressures generated by the explosion. This makes the valve much moredurable and It is also incidental to the presence of this ring valvearrangement of the transfer ports 14-45, and the suction port 19 of thepiston, that I am able to scavenge the cylinder member 15 of thetransfer ports, and to cage therein scavenging charges of air and waterfor 110 double scavenging the explosion cylinder, as

hitherto noted, and which is also highly effective for cooling both thepiston and the cylinder; and, moreover, this is all done,

under the direct action of the engine pis- 115 check action-inof notethat it has the important advantage-of not requir- 12 ing any spring'orthe action of gravity for seating pur'pose's; or, as already stated, itopens and closes, in both directions-of its travel, under thecooperative action of the crank shaft ends of the-differential pistons125 of the two units.

All theadvantages hitherto noted, are independent of the mounting of theengine.

he mounting of the engine-The mounting of the e with its 16, and therelative base or crank 1 o ugpermost also accordscertain imporw badvantages, especially when alcohol or vy hydro-carbon oils are employedas the fuel. These kinds of fuel require pre heating. and that hasusually been done before the introduction of the fuel to the com- 1ssion chamber of the engine. By mountthe engine with its base uppermost,as rated in this case. said kinds of fuel, 3 above named, can beemployed, if des'iiid. and be introduced into the compressi chambers 5from an ordinary vaporizer without pro-heating. Whatever amount of thesefuels come into the compression chainhers 5 in liquidor unvaporized formwill settle, by gravity, into the hottest part of the hollow piston 7and directly onto the piston head, and be there effectively va porizedand forced into the explosion cylinder in the charging action. In otherwords, there is no opportunity for accumulation of the liquid fuelbeyond that incidental to the interval between successive charges. Theposition of the deflector 18, relative to the walls of the piston head,in-

creases this vaporizing or heating action on the fuel. If alcohol shouldbe used, which is.well known to contain 10% or more of water, the waterthereof will be turned into steam'and pass in with the charge. Moreover.the exploslve mixture itself is thus rendered effective for cooling thepiston and cylinder to a large extent. This would be true, to someextent, if the engine was mounted with its base lowermost, or in-thecustomary way, but is effective to a much larger extent when mounted, asshown, with its base uppermost, when alcohol or the heavy hydro-carbonsare employed. Even with gasolene, there can be no flooding of thecompression chambers, when the engine is mounted with its baseuppermost, as shown. and the same remark applies in respect tolubricating oil. This mounting is also important in respect to the useof water with the air drawn into the differential spaces 10 and used forscavenging the transfer ports and the explosion cylinders, ashereinbefore noted. lVhatever water is drawn in with the air through thecomuined air and water valve 23, pipe 24: and connecting port 22 intothe said differentialspaces 10, and is not held in suspension by the.air, will settle, by gravity, against the lower walls of said spaces 10,and flow into the transfer ports or be sucked therein in' the scavengingaction. Moreover, no excess of water can accumulate in the cylindermember 15 of the transfer ports, because when the piston is in itslowermost or exploding position, as shown in the left hand unit in Fig.1, the suction port 19 of the piston connects the cylinder port 15 withthe exhaust chamber 12, thereby permittin the water to escape into theexhaust. It to lows that none of the scavenging water can mix 1. In anexplosive engine, a casing having compression and combustion chambers,an intake port leading to said compression chamber, an exhaust .portfrom said combustion chamber, a passage-way in said casing connectingsaid compression and combustion chambers and a hollow piston having aclosed head and provided with a valved opening in its side forcontrolling said passageway which connects said compression andcombustion chambers, substantially as described. In an explosive engine,a casing-having compression and combustion chambers an intake portleading to said compression chamber, an exhaust port from saidcombustion chamber, a passageway in said casing connecting saidcompression and combustion chambers, a hollow piston having a closedhead and provided with a valved opening in its side for controlling saidpassageway, and an intake valvesubject to the suction action of thepiston for controlling said intake port, substantially as described.

3. In an explosive en no, the combination with a cylinder an pistonhaving in their respective walls coiiperating sections of a transfer ordistribution passageway, of a ring valve seated in said piston andcontrolling said passageway under the motion of the piston,substantially as described.

4.. In a two-cycle explosive engine, the combination with a cylinder'andpiston having cooperating sections of a transfer passageway, of a ringvalve seated between the sections of said passageway with freedom for alimited movement of the piston through said ring valve, whereby thepiston will pick up and drop said ring valve to control said transferpassageway.

5. In a two-cycle explosive engine, having a. compression chamber, thecombination with a cylinder and piston having in their respective .wallscooperating sections of a transfer passageway, of a ring valve seated insaidpiston and controlling said passageway under the motion of thepiston, with said passageway sections and said valve so related that gaswill remain caged in the cylinder section of said transfer passageway,after the charging action is completed, and a suction port in the pistonwall arranged to cooperate with said transfer passageway sections andsaid ring valve to secure the return of said caged gas to thecompression chamber and to refill said cylinder passageway section witha scavenging charge, under the suction action of said piston, stantiallyas described.

6. In a two-cycle explosive engine, having a compression chamber, thecombination with a cylinder and piston having in their respective wallscoiiperating sections of a transfer passageway, of a ring valve seatedbetween the sections of said passageway, with freedom for limitedmovementof the piston through said valve and opera ive thereby tocontrol said passageway, that under the motion of the piston, and withsaid parts so arranged that the gas will remain caged in the cylindersection of said transfer passageway, after the charging-action iscompleted, and a suction port in said piston arranged to coiiperate withsaid transfer passageway sections and said ring valve to secure thereturn of said caged gas to the compression chamber and to refill saidcylinder passageway section with a scavenging charge, under the suctionaction of said piston, substantially as described.

7 A crank case or base compression twocycle explosive engine having inits cylinder and piston walls cooperating sections of a transferpassageway, a ring valve seated between the piston and cylinder andopercopies of this patent may be obtained for ive cents each, byaddressing the subgine having ated by the piston to control saidpassage= way, and which engine is mounted with its base or crankuppermost and has a hollow piston open to the crank case or compressionchamber and is provided with a deflector in the interior of said hollowpiston arranged to deflect the explosive material over the hottest partof the piston head in its passage through said transfer passageway,substantially as described.

8. In a two-unit two-cycle explosive entwo explosion and compressionchambers, the combination with the two pistons coupled to the commoncrank shaft, substantially 180 degrees apart, of a fuel supply valvecasing communicating with the two compression chambers a two-way checkvalve located in said casing'and subject to the suction and compressionactions of said two pistons to shift the fuel supply alternately fromone to the other of said compression chambers, and also provided with anadjustable governing stop operative to limit the closing movement ofsaid check valve to govern the speed of the engine, substantially asdescribed.

In testimony whereof I affix my signature in presence of two witnesses.

ELLIs J. w OOLF.

Witnesses:

JAs. F. WILLIAMSON, H. D. KILGORE.

Commissioner of 2mm.

Washington, D. 0.

